This section provides background information related to the present disclosure which is not necessarily prior art.
In automotive vehicles, it is common to have a series of different heat exchangers transferring heat to or from a variety of liquids or gases. A typical vehicle may contain a heat exchanger to cool a fluid that is used to cool an engine. Charge air coolers are used to cool the air that is being compressed before leading into the intake of an engine. Additional heat exchangers may be used to cool oil that lubricates the internal components of the engine; additionally transmission fluid may also flow through a heat exchanger to maintain the transmission at an optimum temperature. Typical construction of such heat exchangers generally have an inlet or an outlet on one or both of the heat exchanger tanks and may have a fixed baffle to accommodate packaging constraints or increase heat rejection. The baffle is fixed so that the medium entering the inlet passes through a fixed number of tubes and the medium exiting has passed through a fixed number of tubes.
A problem with the conventional fixed baffle heat exchangers is their lack of versatility. Heat exchangers are optimally designed for one application only in accordance with the flow parameters and heat exchange requirements expected in that application and in an optimum condition. Where the heat exchanger designed for one application is used in another application in which the flow rate of the medium to be cooled is greater than the design flow rate, there is usually an unacceptable pressure drop in the system. Or if the viscosity of the fluid can change based on temperature, like oil, there may be an unacceptable pressure drop as well. If, on the other hand, the heat exchanger is used in an application in which the flow rate is less than the design flow rate, there is inefficient heat transfer to the cooling medium.
Heat exchangers with fixed baffle arrangements lack versatility in that it is not possible to cater for different flow parameters and heat exchange requirements. Also if the viscosity of a liquid can change based on its temperature the heat exchanger with fixed baffles cannot adjust to maximized optimum fluid flow limiting pressure drop losses.
A current solution is to install a bypass system. This system would allow the medium, during certain conditions, to bypass the heat exchanger entirely until the correct conditions are met. Such systems add complex components like control modules with sensors to regulate the system driving up overall costs and difficulty in implementation. However, if the heat exchanger was versatile to change the internal baffle position to allow for greater flow during high viscosity period and regulate to an optimum flow during normal operation, there would be no need for complex solutions.
It would be desirable to have a heat exchanger which has greater versatility, and the present development seeks to provide such a heat exchanger.